JP3129589B2 - Paint composition - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a coating composition, for example, a clear type coating composition.

[0002]

2. Description of the Related Art Conventionally, urethane tanks used for interior and exterior parts of automobiles are generally two-part curable urethane paints of acrylic polyol and polyisocyanate.

[0003]

However, since the conventional urethane paint has a low coefficient of friction as a cured coating film property and a small elastic deformation property, small articles such as a console box or a small container coated with the paint are used. In a truck or the like that is slippery, especially when the vehicle is running with a large amount of vibration, there is a disadvantage that small objects placed in a console box or the like may slide down during traveling. Therefore, an object of the present invention is to provide a coating composition having a higher coefficient of friction than a conventional urethane coating.

[0004]

Means for Solving the Problems In order to solve the above problems, a coating composition according to claim 1 is a coating composition containing a polyurethane resin obtained by reacting a polyester polyol and a polyisocyanate as a main component, The polyurethane resin has a weight average molecular weight of 1,000 or more and 20,000 or less, a hydroxyl value of 20 or more and 200 or less, a breaking elongation of a cured coating film of 50% or more and 200% or less, and a breaking strength of 120 kg / cm ² or more and 300 kg. / Cm ² or less, and the compression set is 30% or more and 60% or less.

The polyester polyols include one or more of phthalic acid, isophthalic acid, tetrahydrophthalic acid, maleic acid, metaconic acid, citraconic acid, itaconic acid, adipic acid and sebacic acid, and ethylene glycol, diethylene glycol, Triethylene glycol, propylene glycol, 1.6-hexanediol, trimethylolpropane, glycerin, pentaerythritol, cyclohexanedimethanol, bishydroxyethoxybenzene, N-alkyldiethanolamine, and their multimers (dimers, octamers, etc.), etc. As a reaction product with one or more of the polyhydric alcohols.

The polyisocyanate includes:
Organic diisocyanates such as hexamethylene diisocyanate, metaxylene diisocyanate, tolylene diisocyanate, isophorone diisocyanate, 4.4'-methylenebis (cyclohexyl isocyanate), dimer acid diisocyanate, and the reaction products of these compounds with polyhydric alcohols.

As a method for obtaining the reaction product of the polyester polyol and the polyisocyanate, various known methods can be used, such as the type of the both reactants used and the desired degree of polymerization. Is appropriately selected in consideration of In the reaction between the polyester polyol and the polyisocyanate, a chain extender can be used to increase the degree of polymerization of the polyurethane resin to be produced. Examples of the chain extender include low molecular weight diamines such as ethylenediamine, propylenediamine, isophoronediamine, cyclohexanediamine, 2.4.4-trimethylhexamethylenediamine, and xylylenediamine. Further, alkanolamines such as aminoethanol, aminoethoxyethanol and diethanolamine, monoamines such as ethylamine and butylamine, and the above-mentioned low molecular weight diols such as ethylene glycol can be used in combination with these low molecular weight diamines. Further, as a catalyst used when reacting a polyester polyol and a polyisocyanate, a catalyst for a normal urethane-forming reaction can be used. Iron acetylacetonate, triethylamine and the like. The reaction conditions between the polyester polyol and the polyisocyanate are set so that the resulting polyurethane resin has a hydroxyl value in the range of 20 to 200 in terms of resin solids. Further, it is preferable that the molecular weight is set so as to be 1,000 or more and 20,000 or less.

[0008] The hydroxyl value in terms of resin solid content of the polyurethane resin is set to 20 or more and 200 or less when this value is 20 or less.
If it is smaller, the coefficient of friction of the resin will be small, while if it is larger than 200, the tackiness of the resin will be large.

The average molecular weight of the polyurethane resin is generally from 1,000 to 20,000. This is the molecular weight of a generally available polyurethane resin, which may be higher than 20,000, but has the disadvantage of increasing costs.

[0010] The polyurethane resin cured film properties include a breaking elongation of 50% or more and 200% or less and a breaking strength of 1%.
20 kg / cm ² or more 300 kg / cm ² or less and compression set 30% or more 60
% Or less (20 ° C.), and it is difficult to obtain a high coefficient of friction and abrasion resistance with a coating film outside the above range, and the coating workability such as uniform coating property is reduced.
In this specification, the breaking elongation and breaking strength are values measured using a tensile tester Tensilon Autograph IM-100 manufactured by Shimadzu Corporation under a measuring condition of a tensile speed of 50 mm / min and a temperature of 20 ° C., The compression set is a value measured according to JIS K6301.

On the other hand, the static friction coefficient of the polyurethane resin is optimally 0.8 to 1.5 (20 ° C.).
If it is 0.8 or less, the anti-slip effect is weak, and if it is 1.5 or more, the adhesiveness in a high temperature region (30 ° C. or more) becomes large, and the coating film strength decreases. In the present specification, the coefficient of static friction is a value measured using a friction angle measuring instrument (AN-F type) manufactured by Toyo Seiki Co., Ltd.

The coating composition of the present invention is usually used as a solvent coating. As the solvent, any of those generally used for paints can be used, for example, aromatic hydrocarbons,
Examples thereof include various organic solvents such as aliphatic hydrocarbons, esters, and ketones. In addition, an extender pigment, a coloring pigment, a leveling agent, an antioxidant, and the like may be added to the coating composition of the present invention as needed.

The coating composition according to the first aspect can be applied by a commonly used method. Desirable methods include an air spray method, an airless spray method, and a flow coater method. The coating composition according to claim 1 applied to an object to be coated is cured at a temperature of from room temperature to 100 ° C. to form a restorable coating film on the object to be coated. The coating composition described in claim 1 is applicable to objects to be coated of various materials such as wood, ceramic, metal, and plastic.

[0014]

According to the restorable coating composition of claim 1,
This polyurethane resin is a reaction product of a polyester polyol and a polyisocyanate, and further contains a hydroxyl group having a hydroxyl value of not less than 20 and not more than 200 in terms of resin solid component. Coefficient of static friction is greater than

[0015]

EXAMPLE 100 parts by weight of a base material having the composition shown in Table 4 was used, and a, b, and c having the composition shown in Table 2 were used as curing agents.
Parts by weight, and using the thinner having the composition shown in Table 3 as a solvent.
20 parts by weight were mixed to obtain each coating composition. Spray pressure of each paint obtained using a spray gun with a diameter of 1.0 to 1.2 mmφ
3.5 ~ 4.0kg / cm ² , setting 10min, drying at 80 ℃
The coating was performed on an ABS resin plate under the conditions of 30 minutes and a film thickness of 25 to 30 μm.

[0016]

[Table 1]

In Table 1, the numerical units are parts by weight, alloplats OB-6080 and OB-6045 are soft polyester polyol resins (manufactured by Nippon Shokubai Co., Ltd.) having different modified formulations, respectively, and OB-6080 is non-volatile. OB-6045 has a non-volatile content of 80.0% and a hydroxyl value of 40.
It is.

[0018]

[Table 2]

In Table 2, numerical units are parts by weight, and Barnock DN-980 is a polyisocyanate resin manufactured by Dainippon Ink and Chemicals, Inc. (nonvolatile content 75.0%, isocyanate group
Mytec NY-718A is a soft type polyisocyanate resin (75.0% non-volatile content and 7.0% isocyanate group) manufactured by Mitsubishi Kasei Kogyo Co., Ltd.

[0020]

[Table 3]

[0021]

[Table 4]

In Table 4, the numerical unit is g, and Megafac F-173 (manufactured by Dainippon Ink and Chemicals, Inc.) is a perfluoroalkyl group-containing oligomer (butyl acetate 20% solution), and has a defoaming property. It is a coating film surface conditioner having. In Table 4, dibutyltin dilaurate (butyl acetate 1
% Solution) is a curing catalyst. In Table 4, the polyester polyol resin is a resin having the composition shown in Table 1. Main agent A,
Table 5 shows the static friction coefficient of each coating film obtained by each combination of B and C and the curing agents A, B, and C.

[0023]

[Table 5]

As shown in Table 5, A, B, C and A,
All of the coating films in which b and c are mixed have a higher coefficient of static friction than the coating film of the conventional urethane tank. However, B-C, C-A, C-B, and C-
In the coating film of (c), the resulting coating film has a strong tackiness, so that a combination of A-A, A-B, B-A, A-C and B-B is practical, and adhesion of dust and dust is reduced. The combination of A-i is optimal because it is smaller. The breaking elongation of the coating film of the combination of A-A, A-B, B-A, A-C, and B-B is 50 to 200%, and the breaking elongation is 120 to 300 kg / cm ² . The compression set is a value within each range of 30 to 60%, and the hydroxyl value of these paints in the range of 20 to 200 in terms of the resin solid component, and the molecular weight is
More than 1,000 and less than 20,000.

For comparison, the characteristic values of a general urethane paint are as follows: elongation at break: 8 to 10%; strength at break: 310 to 330 kg /
cm ² , compression set 8% and coefficient of static friction 0.40.

[0026]

According to the coating composition of the present invention, since the coefficient of static friction of the coating film is larger than that of the conventional urethane coating, the object is prevented from sliding off the coating film. Therefore, the coating composition of the present invention is suitable for use in painting a console box or accessory case of a vehicle.

──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Takashi Mizoguchi 6-21 Hatata-cho, Ibaraki-shi, Osaka Inside Ohashi Chemical Industry Co., Ltd. (72) Yoshihisa Kawada 6-21 Hatata-cho, Ibaraki-shi, Osaka Ohashi Chemical Industry (56) References JP-A-64-75571 (JP, A) JP-A-5-51556 (JP, A) JP-A-6-207141 (JP, A) (58) Fields studied (Int. Cl. ⁷ , DB name) C09D 175/04

Claims (1)

(57) [Claims] 1. A coating composition comprising a polyurethane resin as a main component obtained by reacting a polyester polyol and a polyisocyanate, wherein the polyurethane resin has a weight average molecular weight of 1,000 to 20,000 and a hydroxyl value of 20.
Not less than 200 and the breaking elongation of the cured coating film is 50
% To 200% or less, and the breaking strength is 120 kg / c.
m ² or more and 300 kg / cm ² or less, and a compression set of 3
A coating composition having 0% or more and 60% or less.